Bird Technologies' Thruline 4027A2M is a directional RF power sensor head for CW measurements, designed for high-precision forward and reflected power in the 1.5–2.5 MHz band and capable of handling 3 W to 10 kW in a single through path. It is intended for integration with Bird's Thruline power meters/display units and is widely used in semiconductor processing and other precision process applications where stable, traceable RF power readings are required. The 4027A2M variant is documented as CALDATA included to simplify quick calibration, and it is one of the CW RF power sensors in the 4027A Series.
